In general such coaxial short-circuit devices have an inner and an outer conductor which are connected via a shorting plunger in an electrically conductive manner.
In a known short-circuit device, the shorting plunger is adjustable along a rod which is guided toward the outside. This arrangement has the drawback, however, that a considerable demand of space is required when using a shorting plunger which has a long adjusting path between two end positions in dependence on the electrical length of the conductor since the stroke of the rod outside the short-circuit device is equal to the maximum adjusting path of the shorting plunger.
It is also known to adjust the shorting plunger via a driving mechanism which is coaxially arranged with respect to a short-circuit device either inside or outside of the latter. The drive mechanism is connected with the shorting plunger through slots which are arranged in the inner or outer conductor.
The provision of such slots is disadvantageous since the characteristic impedance of the short-circuit device is altered and thus causes considerable high-frequency losses.